Pumps for expressing milk from breasts are well-known. One known breast pump is disclosed in Whittlestone U.S. Pat. No. 4,607,596.
The Whittlestone patent discloses a breast pump having two milk collectors connected to a pump which applies both a vacuum and pulsating pressure to the breasts to extract milk. The pulsating pressure massages the breast to stimulate milk production, and the vacuum secures the milk collectors to the breasts and helps draw the milk and collect it. However, the vacuum at the two collectors can only be adjusted at the pump, and cannot be individually adjusted. This can create discomfort for the user if one breast is more sensitive than the other, or responds to stimulation differently than the other. Thus, there is a need for breast pumps having individual control of two collectors, which is more comfortable for the user.
The Whittlestone patent does not disclose a vacuum release for the collectors. As a result, when the device is turned off, the vacuum is broken by pulling the collectors from the breasts, or waiting for the vacuum to dissipate in order to remove the collectors. This is inconvenient and sometimes uncomfortable. Thus, there is a need for breast pumps having a vacuum release, preferably in a convenient location such as the collectors themselves.
In the Whittlestone device, milk from the two collectors is commonly drawn into a first collection vessel, and then a second collection vessel. The milk is drawn through vacuum lines, though, which makes cleaning difficult. Moreover, the milk collecting vessels are reusable, and require frequent and thorough cleaning. Accordingly, there is a need for breast pumps which are more sanitary and easier to clean than the Whittlestone device.
The Whittleson patent discloses a breast cup having a housing, a relatively soft inner ring or donut, and a flexible liner. The liner wraps around the outlet of the cup, and a bung is inserted into the cup outlet to pass the vacuum and milk. At the inlet side, the liner is simply folded over the outside of the housing. This design has limitations. The liner is not accurately aligned and reliably sealed on the inlet side, so moisture and other contaminants can get inside the liner, which is undesirable. At the outlet, the liner can collapse around the entire breast, including the tip of the nipple, which can be uncomfortable and can cause unnecessary trauma. Accordingly, there is a need for breast pumps having cups which better fix the liner to the housing. There is also a need for breast pump cups which protect at least the end of the nipple from discomfort due to pulsating pressure.
The breast pump disclosed in the Whittlestone patent is a diaphragm pump operated by an electric motor. Rotation of the motor shaft is translated into back and forth action by a somewhat large and cumbersome linkage which moves the diaphragm. This adds not only size but weight to the pump, as well. This is a problem because storage and portability are desirable to breast pump users. Thus, there is a need for breast pumps which are lighter and smaller than known devices.
Accordingly, one object of this invention is to provide new and improved apparatus for extracting milk from breasts.
Another object is to provide new and improved breast pumps which are more convenient and comfortable to use.
Another object is to provide new and improved breast pumps having collectors with individual vacuum adjustments for each collector, and at least one vacuum release.
Still a further object is to provide new and improved breast pumps which are more sanitary, easy to clean and easy to disassemble and assemble.
Another object is to provide new and improved breast pumps which are more comfortable to use.
Yet another object is to provide new and improved breast pumps which are relatively light, compact and portable.